8Modul A: Bioorganische Chemie und Naturstoffchemie, SS 2005, H. DModul A: Bioorganische Chemie und Naturstoffchemie, SS 2005, H.D.Martin, Kapitel 01_AromatenPLANT PIGMENTSFlavonoids and anthocyanins are conspicuous plant pigments in nature thatare responsible for the beauty and splendor of flowers, fruits, fruit tree blossomsand of the autumn leaves.Flavones are responsible for the yellow and orange colors; and the anthocyaninsare the source of red, violet and blue colors. These compounds occur mainly inhigher plants and are less common in the lower orders. You don’t find them inalgae, fungi or bacteria.The flavonoids play a major role in attracting insects to feed and pollinate theseplants. Some of them also have a bitter taste and repel harmful insects likecaterpillars.Flavonoids are thought to be antioxidants, and play a major role in our diet,preventing the ravages of aging caused by free-radicals.These compound have their biosynthetic origin in both the skimic acid pathwayand the acetogenin pathway - they are of hybrid origin.